Am I wrong for not wanting extended family at baby’s first birthday

So my baby boy is turning one this month and my aunt and I have begun prep for it a few months ago. The space we’re renting is quiet pricey but it was all I could find on a short notice. I don’t want to invite a lot of people just about 10 immediate family members,2 of (our) friends and about 5 other extended family members on my side of the family. I’m also planning to invite my partners mother, 2 siblings one with children and the other with a girlfriend. We’re also inviting partners father. That makes about 25 people. So I have my partner send the invitation to his mother father and siblings via text. Turns out today when I went to visit sister and mother they had already had a chat about sending out the invitation to the rest of their family memebers (aunts,uncles and siblings that have never even my son) to say that I was annoyed was an understatement because they were a tap away from sending it till partner intervened and said we were trying to keep the party to a minimum because little one also doesn’t feel comfort around new people and strangers. He’s a shy baby. Well after we leave the house his sister starts bombarding him with messages that said “do you not want moms family at the party” followed with spam calls from his mother. I feel bad but at the same time I’m only inviting people who have made an effort to be interested in my son and his well being. Partner says I’m being ridiculous but am I really ?